W hen the painter Joan Mitchell offered John Cheim his choice of any work of art from her studio, he selected Sunflowers. Fittingly for the artist’s longtime friend and art dealer, Cheim had singled out one of Mitchell’s final masterpieces, a visceral diptych of entangled colors on par with the greatest works by Van Gogh or Monet. That painting – which has since been exhibited at the Museum of Modern Art, the National Gallery of Art in Washington, DC, the Pompidou and more – is now coming to auction during The New York Sales.

Sunflowers is just one of many artworks offered from John Cheim’s private collection on 15-16 November at Sotheby’s. The art-world titan who pioneered the “white cube” style gallery is respected as much for his discerning eye as his dedication to the artists he represents – facets embodied by his marvelous collection. “He was all in,” says Sotheby’s Chairman Lisa Dennison. “He not only gave them amazing shows at the gallery and created extraordinary publications, but then lived with them, bought them, in his own environment, in his own home.”

Within three years of joining the Robert Miller Gallery in the 1980s, Cheim was named director – a position he occupied for two decades. There he organized the first ever survey of Jean-Michel Basquiat’s drawings, three of which are now heading to the block at Sotheby’s.

“One of many hallmarks of the gallery’s innovative programming was their passionate and unwavering dedication to female artists,” says Dennison. At both Robert Miller and Cheim & Read, the influential Manhattan gallery he and Howard Read cofounded in 1997, Cheim would go on to build a reputation as an unparalleled representative of artists, serving not only as an early exponent of seminal figures such as Louise Bourgeois, Jenny Holzer and Linda Benglis, but also a close personal friend. “John not only recognizes talent but he knows how to nurture it,” Dennison continues. “He has a unique gift for relationships, creating deep bonds of trust with the artists he champions.”

The selection arriving at Sotheby’s – which also includes works by Alice Neal, Ron Gorchov and more – is collectively titled “A Life of Beauty,” testifying to the depth of commitment that few other collectors achieve.

A Life of Beauty: The Collection of John Cheim

_{Banner: A portrait of John Cheim by Robert Mapplethorpe hangs in the collector’s Manhattan loft.}